Written surveys and assessments are routinely administered by providing users (respondents) with response sheets including pre-printed artwork and locations for the user to enter responses to survey questions or items presented in the assessment. Pre-printed artwork on a response sheet comprises matter printed on each sheet prior to distribution to the respondents and includes information not typically needed to evaluate the user's response(s). Pre-printed artwork may include alphanumeric text, such as survey or test identification information, response instructions, or survey or test questions, graphics (including charts, tables, graphs, and diagrams), graphic features (such as lines, borders, shading, and bubble targets (circles, ellipses, ovals, boxes), and letters or numbers within bubble targets. In the context of the present disclosure, a “bubble target” is defined as the printed circle (or ellipse, oval, box, or other closed shape), whether marked or not, on a response sheet, and “response bubble” is defined as the mark made by a person to fill the bubble target. The user enters marks by filling in, e.g., with a no. 2 lead (graphite) pencil, appropriate bubble targets (i.e., by making response bubbles) corresponding to a letter or number entered in a response box above the bubble target or corresponding to answer choices for one or more questions presented in the survey or test. The test sheets are then scanned, and the responses are evaluated automatically by applying a template or optical mark recognition (OMR) techniques to tally or assess each response based on the bubble target that has been filled in.
In the automated response evaluation process, the user marks must be separated from the pre-printed artwork on the response sheet, so the pre-printed artwork is “dropped out” to create a document including only the user response marks, and possibly other necessary information typically used in OMR processing (e.g., sheet identification marks, timing marks, and skew marks).
Conventionally, separating user response marks from background material, such as the pre-printed artwork, requires the use of an infrared scanner and non-carbon-bearing inks, so that the pre-printed artwork is not included in the scanned document image. Most colored inks used for the pre-printed background artwork are transparent to the wavelength of infrared scanners, while carbon absorbs the light. As a result, the background artwork vanishes, leaving only the graphite responses and other carbon-bearing marks. Thus, a test response sheet including pre-printed artwork and user response marks scanned with an infrared scanner will produce a document that includes only the user response marks (due to infrared light being sensitive only to carbon-bearing inks) and necessary pre-printed marks configured to be detected by an infrared scanner (e.g., sheet identification marks and timing marks). Then OMR is employed to evaluate only the user response marks without interference from the pre-printed artwork.
The necessity of using infrared scanners to separate user response marks from pre-printed artwork creates a number of disadvantages due in part to the high cost of infrared scanners. Infrared scanners are typically much more costly than conventional visible-light scanners (∞$100,000). Exemplary OMR infrared scanners include the iNSIGHT™ 150 by Scantron. Further, the maintenance costs of infrared scanners are high. Infrared scanners are not commonly owned by scanning companies, schools, or other businesses that require scanning of response sheets. This limits or prevents collaborations with groups that do not own infrared scanners, prevents the use of hand-held scanning devices at the survey room or classroom level, and prevents local scanning at the response-collection sites using ordinary, inexpensive scanners.
Software configured to numerically drop out specific background color or color sets from a scanned document has existed from some time. For example, Dunord Technologies does this in its product called ColErase. Other companies, such as Hewlett-Packard and Kofax, also offer background drop-out as a way to increase accuracy of data capture from scanned forms. Existing color drop-out technology, however, requires that the pre-printed content to be dropped out be a different color than the response marks, and often it requires advance knowledge of which color(s) is (are) to be dropped out.
Accordingly, it would be desirable to have systems and processes for processing response forms in a manner that distinguishes the response marks from the pre-printed text and graphics (i.e., background) using standard scanners that are less expensive to purchase and maintain, and that does not require advance knowledge of the colors or shapes of the background elements to be dropped out.